Resize Image in KB

1. Choose your image

Drop a photo or signature or tap to choose

JPG, PNG, WebP (and HEIC where your browser supports it) · you can also paste with Ctrl+V

2. Target file size

Minimum KB (0 = none)

Maximum KB

How the form counts a KB

Output format

3. Dimensions (optional)

Allow smaller pixel size if quality alone cannot reach the maximum (turned off automatically when exact dimensions are set) Signature cleanup: whiten paper, darken ink, trim empty margins Black & white (grayscale)

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Privacy: Your photo is decoded and re-encoded with the canvas API inside your browser. It is never uploaded to ITCOH or anyone else, and re-encoding also drops EXIF data such as GPS location.

Resize an image to an exact KB size for online forms

Online application forms for exams, jobs, scholarships, banks and government services usually reject a photo or signature that is above a maximum file size, and sometimes one that is below a minimum. This tool lets you set both limits at once. It tries the highest JPEG quality that fits, lowers the pixel size only when needed, and can lift a too-small file over the minimum without changing how it looks.

How it works

Quality first: a binary search over JPEG quality finds the sharpest version under your maximum.
Size second: if even low quality is too large, the image is scaled down step by step (unless you fixed the dimensions).
Minimum size: if the file is below your minimum at full quality, a comment block is added inside the JPEG so the byte count reaches the minimum. The pixels stay the same.
KB counting: the default mode treats the maximum as 1000-byte KB and the minimum as 1024-byte KB, so the file passes whichever way the portal counts.

Common size conversions

Print size	At 200 DPI	At 300 DPI
3.5 × 4.5 cm	276 × 354 px	413 × 531 px
2 × 2 inch (51 × 51 mm)	400 × 400 px	600 × 600 px
3.5 × 1.5 cm (signature)	276 × 118 px	413 × 177 px

Always follow the exact numbers in the official notification or on the portal's upload page; requirements differ between forms and change from year to year. Need a full passport-style photo with background and print sheet? Use the passport photo generator. Have an iPhone HEIC photo? Convert it with HEIC to JPG first.

Frequently asked questions

How do I compress an image to 20KB or 50KB?

Choose the image, tap the 20KB or 50KB preset (or type your own max KB) and press Resize. The tool searches for the highest JPEG quality that fits under the limit, and only shrinks the pixel size if quality alone cannot get there.

Can I increase the image size in KB to meet a minimum?

Yes. Set a minimum KB. The tool first raises quality, and if the file is still too small it adds a harmless comment block inside the JPEG so the file reaches the minimum without changing how the picture looks.

Does the form count 1 KB as 1000 or 1024 bytes?

Portals differ. By default the tool keeps the file under the maximum counted in 1000-byte KB and above the minimum counted in 1024-byte KB, so the result passes either way.

How do I make a signature 10KB to 20KB?

Tap the Signature 10–20KB preset. It turns on signature cleanup, which whitens the paper background, darkens the ink and trims empty margins before compressing.

Can I set the photo size in centimetres?

Yes. Pick the cm option, enter width, height and DPI (for example 3.5 × 4.5 cm at 200 DPI), and the tool converts that to pixels and writes the DPI into the JPEG.

Is my photo uploaded to a server?

No. Everything runs in your browser with the canvas API. The photo never leaves your device, which matters for ID photos and signatures.

Where do I find the exact size my exam or job form needs?

Always use the numbers in the official notification or the upload page of the portal. Requirements change between years and forms, so this page does not guess them for you.